Equipment and Leasehold Improvements (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 20,376	$ 20,250
Less: Accumulated depreciation and amortization	(18,981)	(18,389)
Property, Plant and Equipment, Net, Total	1,395	1,861
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	14,587	14,562
Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	790	778
Office Furniture [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	110	110
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	4,815	4,789
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 75	$ 11